Developing method, computer-readable storage medium and developing apparatus

ABSTRACT

A developing method includes: forming a liquid pool of a diluted developing solution diluted with pure water in a central portion of a substrate; forming a liquid film of the diluted developing solution on a surface of the substrate by accelerating rotation of the substrate to diffuse the liquid pool of the diluted developing solution on the entire surface of the substrate; and then supplying a developing solution onto the substrate. Supplying a developing solution includes: supplying the developing solution from a developing solution supply nozzle having a liquid contact surface while securing a gap having a predetermined size between the developing solution supply nozzle and the substrate; and moving the developing solution supply nozzle in a radial direction passing through a center of the substrate while forming a liquid pool of the developing solution between the substrate and the liquid contact surface of the developing solution supply nozzle.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Japanese Patent Application Nos.2014-243139 and 2015-212830, filed on Dec. 1, 2014 and Oct. 29, 2015,respectively, in the Japan Patent Office, the disclosures of which areincorporated herein in their entirety by reference.

TECHNICAL FIELD

The present disclosure relates to a developing method for developing asubstrate, on which a resist film is formed, and forming a predeterminedpattern on the substrate, a computer-readable storage medium and adeveloping apparatus.

BACKGROUND

For example, in a photolithography process of a semiconductor devicemanufacturing process, a predetermined resist pattern is formed on awafer by sequentially performing, for example, a resist coating processof coating a resist liquid on a semiconductor wafer (hereinafterreferred to as a “wafer”) as a substrate to form a resist film, anexposure process of exposing a predetermined pattern in the resist film,a heating process (post-exposure baking process) of promoting a chemicalreaction within the resist film after the exposure, a developing processof developing the exposed resist film, and so forth.

As developing methods, there are known a method of, while supplying adeveloping solution from a long nozzle having a length substantiallyequal to a diameter of a wafer, parallel-moving the nozzle from one endportion of the wafer toward the other end portion thereof, and a methodof supplying a developing solution onto a wafer rotating at a high speedand diffusing the developing solution.

However, when the developing process is performed by the long nozzle, adifference in the developing solution contact time is generated in oneend portion and the other end portion of the wafer. Furthermore, evenwhen the developing solution is supplied to the center of the rotatingwafer, a difference in the developing solution contact time is generatedin the central portion of the wafer and the outer peripheral portionthereof. As a result, a variation in the line width of the resistpattern subjected to the developing process is generated within a waferplane. Along with the recent miniaturization of a resist patternattributable to the high integration of a semiconductor device, thevariation in the line width caused by the difference in the developingtime has become impermissible.

Thus, in order to uniformly perform a developing process within a waferplane, study has been made on a method of using a developing solutionsupply nozzle (hereinafter often referred to as a “PAD nozzle”) having aliquid contact surface, for example, parallel to a substrate.Specifically, a developing solution is first supplied onto a substrate,which is not rotating, while securing a gap of a predetermined sizebetween the liquid contact surface of the developing solution supplynozzle and the wafer, thereby forming a liquid film of the developingsolution between the developing solution supply nozzle and the wafer. Atthis time, the developing solution supply nozzle is positioned in thecentral portion of the substrate. Then, the wafer is rotated at a lowspeed of about 30 rpm. While continuing to supply the developingsolution from the developing solution supply nozzle, namely whilemaintaining the liquid film of the developing solution between thedeveloping solution supply nozzle 300 and the substrate, the developingsolution supply nozzle 300 is moved to the outer peripheral portion ofthe wafer W as illustrated in FIG. 25. This makes it possible to supplythe developing solution Q onto the entire surface of the wafer W and torealize a uniform developing process within a wafer plane.

From the viewpoint of improving the throughput of wafer processing, itis preferred that the developing time is as short as possible. However,according to the study conducted by the present inventors, it wasconfirmed that if the developing time is made short in a developingprocess which makes use of a PAD nozzle, the points at which the linewidth of a resist pattern does not become a desired value are spirallygenerated within a wafer plane, for example, as illustrated in FIG. 26.In FIG. 26, the line width of a resist pattern within a wafer plane ismeasured at multiple points on a shot-by-shot basis and the degree ofvariation in the line width in each shot is illustrated by colorshading. In addition, FIG. 26 illustrates a case where the developingtime is, for example, 30 seconds. However, it was confirmed that, if thedeveloping time is 60 seconds, as illustrated in FIG. 27, the tendencyto become spiral is scarcely seen and the line width within the waferplane is substantially uniform.

SUMMARY

Some embodiments of the present disclosure provide a developing methodand a developing apparatus capable of improving the throughput of adeveloping process while securing the in-plane uniformity of thedeveloping process.

The present inventors have made extensive investigation on the causes ofvariation in the line width spirally generated when the developing timeis shortened. As a result, the present inventors have found that thespiral shape illustrated in FIG. 26 is attributable to the dissolvedproduct generated at an initial stage of development. Furthermore, thereason why the tendency of the spiral shape is not generated when thedeveloping time is about 60 seconds as mentioned above is considered tobe that the developing time is sufficiently secured and the influence ofthe dissolved product is relatively small.

The present disclosure is based on this finding. According to thepresent disclosure, a liquid pool of a diluted developing solution isfirst formed in a central portion of a substrate. Then, the substrate isrotated to diffuse the liquid pool of the diluted developing solutionover the entire surface of the substrate, thereby forming a liquidsurface of the diluted developing solution on the substrate surface. Atthis time, a dissolved product is generated on the substrate by thediluted developing solution. By rotating the substrate, the dissolvedproduct is removed from the substrate together with the diluteddeveloping solution. Then, a liquid film is formed between thedeveloping solution supply nozzle having a liquid contact surface andthe substrate. While continuing to supply the developing solution fromthe developing solution supply nozzle, the substrate is rotated and thedeveloping solution supply nozzle is moved from the central portion ofthe substrate to the outer peripheral portion of the substrate, therebycoating the developing solution on the entire surface of the substrate.At this time, the developing process is performed without being affectedby the dissolved product because the dissolved product has already beenremoved by the diluted developing solution. As a result, even when thedeveloping time is made shorter than that of the prior art, it ispossible to uniformly perform the developing process within a waferplane. Therefore, according to the present disclosure, it is possible toimprove the throughput of the developing process while securing thein-plane uniformity of the developing process.

According to an embodiment of the present disclosure, there is provideda developing method for supplying a developing solution onto a substrateand developing a resist film formed on the substrate and provided with apredetermined exposed pattern, including: forming a liquid pool of adiluted developing solution diluted with pure water in a central portionof the substrate; after forming the liquid pool, forming a liquid filmof the diluted developing solution on a surface of the substrate byaccelerating rotation of the substrate to diffuse the liquid pool of thediluted developing solution on the entire surface of the substrate; andafter forming the liquid film, supplying the developing solution ontothe substrate. Supplying the developing solution includes: supplying thedeveloping solution from a developing solution supply nozzle having aliquid contact surface while securing a gap having a predetermined sizebetween the developing solution supply nozzle and the substrate; andmoving the developing solution supply nozzle in a radial directionpassing through a center of the substrate while forming a liquid pool ofthe developing solution between the substrate and the liquid contactsurface of the developing solution supply nozzle.

According to another embodiment of the present disclosure, there isprovided a non-transitory computer-readable storage medium which storesa program that operates on a computer of a control part configured tocontrol a developing apparatus so as to cause the developing apparatusto perform the developing method.

According to still another embodiment of the present disclosure, thereis provided a developing apparatus for supplying a developing solutiononto a substrate and developing a resist film formed on the substrateand provided with a predetermined exposed pattern, including: asubstrate holding part configured to hold a rear surface of thesubstrate and to rotate the held substrate about a vertical axis; adeveloping solution supply nozzle including a liquid contact surface anda supply hole configured to supply the developing solution to the liquidcontact surface; a moving mechanism configured to move the developingsolution supply nozzle; a pure water supply nozzle configured to supplypure water onto the substrate; and another moving mechanism configuredto move the pure water supply nozzle.

According to still another embodiment of the present disclosure, thereis provided a developing apparatus for supplying a developing solutiononto a substrate and developing a resist film formed on the substrateand provided with a predetermined exposed pattern, including: asubstrate holding part configured to hold a rear surface of thesubstrate and to rotate the held substrate about a vertical axis; adeveloping solution supply nozzle including a liquid contact surface anda supply hole configured to supply the developing solution to the liquidcontact surface; a moving mechanism configured to move the developingsolution supply nozzle; a diluted developing solution supply nozzleconfigured to supply a diluted developing solution onto the substrate;and another moving mechanism configured to move the diluted developingsolution supply nozzle.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the presentdisclosure, and together with the general description given above andthe detailed description of the embodiments given below, serve toexplain the principles of the present disclosure.

FIG. 1 is a plan view illustrating the schematic configuration of asubstrate processing system according to the present embodiment.

FIG. 2 is a front view illustrating the schematic configuration of thesubstrate processing system according to the present embodiment.

FIG. 3 is a rear view illustrating the schematic configuration of thesubstrate processing system according to the present embodiment.

FIG. 4 is a vertical sectional view illustrating the schematicconfiguration of a developing apparatus.

FIG. 5 is a horizontal sectional view illustrating the schematicconfiguration of the developing apparatus.

FIG. 6 is a perspective view illustrating the schematic configuration ofa developing solution supply nozzle.

FIG. 7 is a flowchart explaining major steps of a wafer processingprocess.

FIG. 8 is a time chart illustrating the rotation speed of a wafer andthe operations of respective parts in a developing process.

FIG. 9 is a vertical sectional explanatory view illustrating a state inwhich a liquid pool of pure water is formed on a wafer.

FIG. 10 is a vertical sectional explanatory view illustrating a state inwhich a dilution-purpose developing solution is supplied onto the liquidpool of pure water.

FIG. 11 is a vertical sectional explanatory view illustrating a state inwhich the diluted developing solution is diffused toward the outerperiphery of a wafer W by rotating the wafer.

FIG. 12 is a vertical sectional explanatory view illustrating a state inwhich a developing solution supply nozzle is moved to above the centralportion of the wafer.

FIG. 13 is a vertical sectional explanatory view illustrating a state inwhich a liquid film of a developing solution is formed between the lowerend surface of the developing solution supply nozzle and the wafer.

FIG. 14 is a vertical sectional explanatory view illustrating a state inwhich the developing solution supply nozzle is moved toward the outerperiphery of the wafer while supplying the developing solution.

FIG. 15 is an explanatory plan view illustrating a state in which thedeveloping solution supply nozzle is moved toward the outer periphery ofthe wafer while supplying the developing solution.

FIG. 16 is an explanatory view illustrating a variation in a line widthof a resist pattern when a developing process is performed by adeveloping method according to the present embodiment.

FIG. 17 is a vertical sectional explanatory view illustrating a state inwhich the diluted developing solution is directly supplied onto a resistfilm.

FIG. 18 is a vertical sectional explanatory view illustrating a state inwhich the dilution-purpose developing solution is supplied by thedeveloping solution supply nozzle.

FIG. 19 is a vertical sectional explanatory view illustrating a state inwhich a liquid pool of the diluted developing solution is formed by thedeveloping solution supply nozzle.

FIG. 20 is an explanatory view illustrating the schematic configurationof a developing solution supply nozzle according to another embodiment.

FIG. 21 is an explanatory view illustrating the schematic configurationof a developing solution supply nozzle according to still anotherembodiment.

FIG. 22 is an explanatory view illustrating the schematic configurationof a developing solution supply nozzle according to still anotherembodiment.

FIG. 23 is an explanatory view illustrating the schematic configurationof a developing solution supply nozzle according to still anotherembodiment.

FIG. 24 is a vertical sectional explanatory view illustrating a state inwhich the developing solution supply nozzle is moved toward the centralportion of the wafer while supplying the developing solution.

FIG. 25 is an explanatory plan view illustrating one example ofdeveloping method which makes use of a PAD nozzle.

FIG. 26 is an explanatory view illustrating a variation in a line widthof a resist pattern.

FIG. 27 is an explanatory view illustrating a variation in a line widthof a resist pattern.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments, examples ofwhich are illustrated in the accompanying drawings. In the followingdetailed description, numerous specific details are set forth in orderto provide a thorough understanding of the present disclosure. However,it will be apparent to one of ordinary skill in the art that the presentdisclosure may be practiced without these specific details. In otherinstances, well-known methods, procedures, systems, and components havenot been described in detail so as not to unnecessarily obscure aspectsof the various embodiments.

FIG. 1 is an explanatory view illustrating the schematic configurationof a substrate processing system 1 provided with a developing apparatuswhich performs a developing method according to the present embodiment.FIGS. 2 and 3 are, respectively, a front view and a rear viewschematically illustrating the internal configuration of the substrateprocessing system 1.

As illustrated in FIG. 1, the substrate processing system 1 has aconfiguration in which a cassette station 10 into and from whichcassettes C each accommodating a plurality of wafers W are loaded andunloaded, a processing station 11 provided with various kinds ofprocessing apparatuses for performing predetermined processes to thewafers W, and an interface station 13 configured to perform the deliveryof wafers W between the processing station 11 and an exposure apparatus12 disposed adjacent to the processing station 11, are integrallyconnected to one another.

A cassette mounting stand 20 is installed in the cassette station 10. Aplurality of cassette mounting plates 21 configured to mount thecassettes C when the cassettes C are loaded and unloaded with respect tothe exterior of the substrate processing system 1 is installed in thecassette mounting stand 20.

In the cassette station 10, there is installed a wafer transfer device23 which is movable along a transfer path 22 extending in an X directionas illustrated in FIG. 1. The wafer transfer device 23 is also movablein an up-down direction and about a vertical axis (in a 0 direction).The wafer transfer device 23 is capable of transferring the wafers Wbetween the cassettes C mounted on the respective cassette mountingplates 21 and a delivery device of a third block G3 of the processingstation 11 which will be described later.

In the processing station 11, there is provided a plurality of, e.g.,four, blocks G1, G2, G3 and G4 which includes various kinds ofapparatuses. For example, the first block G1 is provided at the frontside (at the X-direction negative side in FIG. 1) of the processingstation 11. The second block G2 is provided at the rear side (at theX-direction positive side in FIG. 1) of the processing station 11.Furthermore, the third block G3 is provided at the cassette station 10side (at the Y-direction negative side in FIG. 1) of the processingstation 11. The fourth block G4 is provided at the interface station 13side (at the Y-direction positive side in FIG. 1) of the processingstation 11.

For example, in the first block G1, as illustrated in FIG. 2, aplurality of liquid processing apparatuses, for example, a developingapparatus 30 which subjects the wafer W to a developing process, a lowerantireflection film forming apparatus 31 which forms an antireflectionfilm (hereinafter referred to as a “lower antireflection film”) on alower layer of a resist film of the wafer W, a resist coating apparatus32 which forms a resist film by coating a resist liquid on the wafer W,and an upper antireflection film forming apparatus 33 which forms anantireflection film (hereinafter referred to as an “upper antireflectionfilm”) on an upper layer of a resist film of the wafer W, are disposedin the named order from below.

For example, three developing apparatuses 30, three lower antireflectionfilm forming apparatuses 31, three resist coating apparatuses 32 andthree upper antireflection film forming apparatuses 33 are respectivelydisposed side by side in the horizontal direction. The number andarrangement of the developing apparatuses 30, the lower antireflectionfilm forming apparatuses 31, the resist coating apparatuses 32 and theupper antireflection film forming apparatuses 33 may be arbitrarilyselected.

In the lower antireflection film forming apparatus 31, the resistcoating apparatus 32 and the upper antireflection film forming apparatus33, for example, spin coating which coats a predetermined coating liquidon the wafer W is performed. In the spin coating, for example, a coatingliquid is ejected from a coating nozzle onto the wafer W and is diffusedon the surface of the wafer W by rotating the wafer W. Descriptions willbe made later on the configuration of the developing apparatus 30.

For example, in the second block G2, as illustrated in FIG. 3, there isprovided a plurality of heat treatment apparatuses 40 to 43 whichperforms heat treatments such as heating and cooling of the wafer W.

For example, in the third block G3, a plurality of delivery devices 50,51, 52, 53, 54, 55 and 56 is sequentially provided from below.Furthermore, in the fourth block G4, a plurality of delivery devices 60,61 and 62 is sequentially provided from below.

As illustrated in FIG. 1, a wafer transfer region D is formed in thearea surrounded by the first block G1, the second block G2, the thirdblock G3 and the fourth block G4. In the wafer transfer region D, thereis disposed, for example, a plurality of wafer transfer devices 70 whichincludes a transfer arm capable of moving in the Y direction, the Xdirection, the 0 direction and the up-down direction. The wafer transferdevices 70 are moved within the wafer transfer region D and are capableof transferring the wafers W to predetermined apparatuses disposed inthe first block G1, the second block G2, the third block G3 and thefourth block G4 existing around the wafer transfer region D.

Furthermore, in the wafer transfer region D, a shuttle transfer device80 which linearly transfers the wafer W between the third block G3 andthe fourth block G4.

The shuttle transfer device 80 is linearly movable, for example, in theY direction in FIG. 3. The shuttle transfer device 80 is moved in the Ydirection while supporting the wafer W and is capable of transferringthe wafer W between the delivery device 52 of the third block G3 and thedelivery device 62 of the fourth block G4.

As illustrated in FIG. 1, a wafer transfer device 100 is provided at theX-direction positive side of the third block G3. The wafer transferdevice 100 includes a transfer arm which is movable, for example, in theX direction, the 0 direction and the up-down direction. The wafertransfer device 100 is moved up and down while supporting the wafer Wand is capable of transferring the wafer W to the respective deliverydevices disposed in the third block G3.

In the interface station 13, there are provided a wafer transfer device110 and a delivery device 111. The wafer transfer device 110 includes atransfer arm which is movable, for example, in the Y direction, the 0direction and the up-down direction. The wafer transfer device 110 isconfigured to support the wafer W, for example, by the transfer arm andis capable of transferring the wafer W between the respective deliverydevices of the fourth block G4, the delivery device 111 and the exposureapparatus 12.

Next, descriptions will be made on the configuration of theaforementioned developing apparatus 30. As illustrated in FIG. 4, thedeveloping apparatus 30 includes a processing container 130, theinterior of which is sealable. A loading/unloading gate (notillustrated) for the wafer W is formed on the side surface of theprocessing container 130.

A spin chuck 140 as a substrate holding portion for holding and rotatingthe wafer W is installed within the processing container 130. The spinchuck 140 may be rotated at a predetermined speed by a chuck drive part141 such as, e.g., a motor or the like. An up-down drive mechanism suchas, e.g., a cylinder or the like, is installed in the chuck drive part141. Thus, the spin chuck 140 is movable up and down.

A cup 142 which receives and recovers the liquid scattering or droppingfrom the wafer W is installed around the spin chuck 140. A dischargepipe 143 which discharges the recovered liquid and an exhaust pipe 144which exhausts the internal atmosphere of the cup 142 are connected tothe lower surface of the cup 142.

As illustrated in FIG. 5, a rail 150 extending along the Y direction(the left-right direction in FIG. 5) is formed at the X-directionnegative side (the lower side in FIG. 5) of the cup 142. The rail 150 isformed to extend, for example, from the outside of the cup 142 at theY-direction negative side (the left side in FIG. 5) to the outside ofthe cup 142 at the Y-direction positive side (the right side in FIG. 5).For example, three arms 151, 152 and 153 are installed in the rail 150.

A pure water supply nozzle 154 which supplies pure water is supported onthe first arm 151. The first arm 151 is movable along the rail 150 by anozzle drive part 155 illustrated in FIG. 5. Thus, the pure water supplynozzle 154 may move from a standby part 156 installed outside the cup142 at the Y-direction positive side to a standby part 157 installedoutside the cup 142 at the Y-direction negative side through the upperside of the central portion of the wafer W disposed within the cup 142.

A dilution-purpose developing solution supply nozzle 158 which suppliesa dilution-purpose developing solution in a first liquid pool formingstep to be described later is supported on the second arm 152. Thesecond arm 152 is movable along the rail 150 by a nozzle drive part 159illustrated in FIG. 5. Thus, the dilution-purpose developing solutionsupply nozzle 158 may move from a standby part 160 installed outside thecup 142 at the Y-direction positive side to the upper side of thecentral portion of the wafer W disposed within the cup 142. The standbypart 160 is installed at the Y-direction positive side of the standbypart 156. As the dilution-purpose developing solution, it may bepossible to use, for example, tetra-methyl ammonium hydroxide (TMAH)having a concentration of 2.38%.

A developing solution supply nozzle 161 which supplies a developingsolution is supported on the third arm 153 through a rotary drivemechanism 162. For example, as illustrated in FIG. 6, the developingsolution supply nozzle 161 has a cylindrical shape as a whole andincludes a lower end surface 161 a, for example, parallel to the waferW. The lower end surface 161 a serves as a liquid contact surface whichmakes contact with a developing solution. The lower end surface 161 aneed not be necessarily parallel to the wafer W but may have any shapecapable of forming a liquid film of a developing solution between thelower end surface 161 a of the developing solution supply nozzle 161 andthe wafer W in a developing solution liquid pool forming step to bedescribed later. For example, the lower end surface 161 a may have adownwardly-bulging gentle spherical surface shape or a slant surfaceshape. Furthermore, a supply hole 161 b which supplies a developingsolution is formed in, for example, the central portion of the lower endsurface 161 a of the developing solution supply nozzle 161. The diameterL of the developing solution supply nozzle 161 is set smaller than thediameter of the wafer W. Similar to the developing solution suppliedfrom the dilution-purpose developing solution supply nozzle 158, thedeveloping solution supplied from the developing solution supply nozzle161 may be tetra-methyl ammonium hydroxide (TMAH) having a concentrationof 2.38%. In the present embodiment, the diameter of the wafer W may be,for example, 300 mm and the diameter L of the developing solution supplynozzle 161 may be, for example, 50 mm. In addition, the developingsolution supply nozzle 161 may be made of a material such as, forexample, polytetrafluoroethylene (PTFE) or the like, which has achemical resistance.

The rotary drive mechanism 162 supports the upper surface of thedeveloping solution supply nozzle 161 and may rotate the developingsolution supply nozzle 161 about a vertical axis.

The third arm 153 is movable along the rail 150 by a nozzle drive part163 as a moving mechanism illustrated in FIG. 5. Thus, the developingsolution supply nozzle 161 may move from a standby part 164 installedoutside the cup 142 at the Y-direction negative side to the upper sideof the central portion of the wafer W disposed within the cup 142. Thestandby part 164 is installed at the Y-direction negative side of thestandby part 157. The third arm 153 is movable up and down by the nozzledrive part 163 and is capable of adjusting the height of the developingsolution supply nozzle 161.

The configurations of other liquid processing apparatuses, namely thelower antireflection film forming apparatus 31, the resist coatingapparatus 32 and the upper antireflection film forming apparatus 33, areidentical with the configuration of the above-described developingapparatus 30 except the difference in the shape and number of thenozzles and the liquids supplied from the nozzles. Therefore,descriptions on the configurations of other liquid processingapparatuses will be omitted.

As illustrated in FIG. 1, a control part 200 is installed in thesubstrate processing system 1 described above. The control part 200 is,for example, a computer and includes a program storage part (notillustrated). A program which controls the processing of the wafer Wperformed in the substrate processing system 1 is stored in the programstorage part. Furthermore, a program for controlling the operations ofthe various kinds of processing apparatuses and the drive systems suchas the transfer devices or the like and for implementing abelow-described delamination process in the substrate processing system1 is also stored in the program storage part. The aforementionedprograms are recorded in a computer-readable non-transitory storagemedium such as, for example, a computer-readable hard disk (HD), aflexible disk (FD), a compact disk (CD), a magneto-optical disk (MO), amemory card or the like and may be installed in the control part 200from the storage medium.

Next, descriptions will be made on a wafer processing process performedusing the substrate processing system 1 configured as above. FIG. 7 is aflowchart illustrating major steps of a wafer processing process.Furthermore, FIG. 8 is a time chart illustrating the rotation speed ofthe wafer W and the operations of the respective parts in the developingprocess performed by the developing apparatus 30.

First, a cassette C which accommodates a plurality of wafers W thereinis loaded into the cassette station 10 of the substrate processingsystem 1. The respective wafers W accommodated in the cassette C aresequentially transferred to the delivery device 53 of the processingstation 11 by the wafer transfer device 23.

Then, the wafer W is transferred to the heat treatment apparatus 40 ofthe second block G2 by the wafer transfer device 70 and is subjected totemperature adjustment. Thereafter, the wafer W is transferred to, forexample, the lower antireflection film forming apparatus 31 of the firstblock G1 by the wafer transfer device 70. A lower antireflection film isformed on the wafer W (Step S1 in FIG. 7). Thereafter, the wafer W istransferred to the heat treatment apparatus 41 of the second block G2and is subjected to a heat treatment.

Subsequently, the wafer W is transferred to the heat treatment apparatus42 of the second block G2 by the wafer transfer device 70 and issubjected to temperature adjustment. Thereafter, the wafer W istransferred to the resist coating apparatus 32 of the first block G1 bythe wafer transfer device 70. A resist film is formed on the wafer W(Step S2 in FIG. 7). Thereafter, the wafer W is transferred to the heattreatment apparatus 43 and is subjected to pre-baking.

Next, the wafer W is transferred to the upper antireflection filmforming apparatus 33 of the first block G1. An upper antireflection filmis formed on the wafer W (Step S3 in FIG. 7). Thereafter, the wafer W istransferred to the heat treatment apparatus 43 of the second block G2and is subjected to a heat treatment. Thereafter, the wafer W istransferred to the delivery device 56 of the third block G3 by the wafertransfer device 70.

Then, the wafer W is transferred to the delivery device 52 by the wafertransfer device 100 and is transferred to the delivery device 62 of thefourth block G4 by the shuttle transfer device 80. Thereafter, the waferW is transferred to the exposure apparatus 12 by the wafer transferdevice 110 of the interface station 13 and is exposed in a predeterminedpattern (Step S4 in FIG. 7).

Subsequently, the wafer W is transferred to the heat treatment apparatus40 by the wafer transfer device 70 and is subjected to post-exposurebaking. Thus, the wafer W is subjected to a deprotection reaction by theacid generated in the exposed portion of the resist film. Thereafter,the wafer W is transferred to the developing apparatus 30 by the wafertransfer device 70 and is subjected to a developing process (Step S5 inFIG. 7).

In the developing process, as illustrated in FIG. 9, a predeterminedamount of pure water P is first supplied to the central portion of thewafer W, on which the resist film R is formed, by the pure water supplynozzle 154 (time t₀ to t₁ in FIG. 8). At this time, the pure water P issupplied in a state in which the wafer W is not rotating. Thus, a liquidpool of the pure water P is formed in the central portion of the wafer W(Step T1 in FIG. 7). Furthermore, at Step T1, the wafer W need not benecessarily in the state of not-rotating. The pure water P may besupplied while rotating the wafer W, as long as the wafer W is rotatedat such a low speed that the liquid pool of the pure water P is formedin the central portion of the wafer W.

Next, the supply of the pure water P is stopped. As illustrated in FIG.10, the dilution-purpose developing solution supply nozzle 158 is movedto the upper side of the central portion of the wafer W. A predeterminedamount of dilution-purpose developing solution Q is supplied on theliquid pool of the pure water P (time t₁ in FIG. 8). Thus, thedilution-purpose developing solution Q is diluted by the pure water Pexisting on the wafer W. A liquid pool of a diluted developing solutionM is formed on the wafer W (liquid pool forming step, Step T2 in FIG.7). At this time, the resist film R and the diluted developing solutionM make contact with each other. Thus, the resist film R is slightlydeveloped and a dissolved product U is generated. The dissolved productU stays at the outer periphery side of the liquid pool along with theflow of the diluted developing solution M. In addition, the ratio of thesupply amount of the pure water P and the supply amount of thedilution-purpose developing solution Q, namely the concentration of thediluted developing solution M, is set such that, for example, theconcentration of tetra-methyl ammonium hydroxide (TMAH) becomes lowerthan about 2.38%.

Next, the wafer W is accelerated to a first rotational speed by the spinchuck 140 while continuing to supply the developing solution from thedilution-purpose developing solution supply nozzle 158 (time t₁ to t₂ inFIG. 8). Thus, as illustrated in FIG. 11, the diluted developingsolution M is diffused from the center of the wafer W toward the outerperiphery thereof. As a result, a liquid film of the diluted developingsolution M is formed on the entire surface of the wafer W (liquid filmforming step, Step T3 in FIG. 7). The first rotational speed may be aspeed at which the diluted developing solution M is diffused toward theouter periphery of the wafer W and is discharged to the outside of thewafer W. For example, the first rotational speed in some embodiments maybe from 1,500 rpm to 2,000 rpm. In the present embodiment, the firstrotational speed is 1,500 rpm. Furthermore, the acceleration at the timeof accelerating the wafer W is, for example, 3,000 rpm/second.

If the liquid film of the diluted developing solution M is formed on thewafer W, the resist film R is slightly developed on the entire surfaceof the wafer W. Thus, a dissolved product U is generated. By diffusingthe diluted developing solution M at the first rotational speed which isa relatively high speed, the dissolved product U is discharged from theouter peripheral portion of the wafer W together with the diluteddeveloping solution M. In FIG. 8, during the course of accelerating thewafer W to the first rotational speed, for example, the rotational speedis reduced to 200 rpm after the rotational speed reaches 400 rpm. Byperforming the speed reduction in this way, an inertial force generatedin the circumferential direction of the wafer W as well as a centrifugalforce acts on the diluted developing solution M existing on the wafer W.This makes it possible to more uniformly diffuse the diluted developingsolution M. When accelerating the wafer W to the first rotational speed,it is not necessarily required to perform the speed reductionillustrated in FIG. 8.

After the rotational speed of the wafer W reaches the first rotationalspeed, the rotation at the first rotational speed is maintained for,e.g., 0.5 second. Thereafter, the rotational speed of the wafer W isdecelerated to stop the wafer W. In this case, the deceleration at thetime of decelerating the wafer W is also 3,000 rpm/second (time t₂ to t₃in FIG. 8). During the time period between time t₂ and time t₃, thedeveloping solution is continuously supplied from the dilution-purposedeveloping solution supply nozzle 158.

Next, the wafer W is stopped and the supply of the developing solution Qfrom the dilution-purpose developing solution supply nozzle 158 isstopped. The dilution-purpose developing solution supply nozzle 158 isretracted from above the wafer W. As illustrated in FIG. 12, thedeveloping solution supply nozzle 161 is moved to the upper side of thecentral portion of the wafer W. At this time, a gap having apredetermined size is formed between the lower end surface 161 a of thedeveloping solution supply nozzle 161 and the upper surface of the waferW. The size of the gap is approximately from 0.5 mm to 2 mm.

Subsequently, the developing solution Q is supplied from the developingsolution supply nozzle 161, thereby forming a liquid pool of thedeveloping solution Q between the lower end surface 161 a of thedeveloping solution supply nozzle 161 and the wafer W as illustrated inFIG. 13 (developing solution liquid pool forming step, Step T4 in FIG.7). At the same time, the developing solution supply nozzle 161 startsto be moved from the central portion of the wafer W toward the outerperipheral portion thereof as illustrated in FIG. 14 while rotating thedeveloping solution supply nozzle 161 by the rotary drive mechanism 162.In this case, the developing solution supply nozzle 161 is moved throughthe center of the wafer W. At this time, the rotational speed of thedeveloping solution supply nozzle 161 in some embodiments may be from 50rpm to 200 rpm. In the present embodiment, the rotational speed of thedeveloping solution supply nozzle 161 is 130 rpm. The moving velocity ofthe developing solution supply nozzle 161 toward the outer peripheralportion of the wafer W in some embodiments may be from 10 mm/s to 100mm/s. In the present embodiment, the moving velocity of the developingsolution supply nozzle 161 is 15 mm/s. Furthermore, the rotationdirection of the developing solution supply nozzle 161 is set to becomeopposite to the rotation direction of the wafer W. This makes itpossible to stir the developing solution Q on the wafer W and to performthe developing process with increased in-plane uniformity.

Simultaneously with the start of supply of the developing solution Qfrom the developing solution supply nozzle 161, the wafer W isaccelerated to a second rotational speed lower than the first rotationalspeed (time t₃ to t₄ in FIG. 8). For example, the second rotationalspeed in some embodiments may be from 15 rpm to 30 rpm. In the presentembodiment, the second rotational speed is 30 rpm. Furthermore, theacceleration at the time of accelerating the wafer W is, for example,3,000 rpm/second. Thus, as illustrated in FIG. 15, the developingsolution Q is gradually supplied from the central portion of the wafer Wtoward the outer periphery thereof.

If the developing solution supply nozzle 161 comes close to the outerperipheral portion of the wafer W, the rotational speed of the wafer Wis decelerated to a speed lower than the second rotational speed, forexample, 15 rpm (time t₅ in FIG. 8). At this time, the deceleration is,for example, 100 rpm/second. In this way, by reducing the rotationalspeed of the wafer W after the developing solution supply nozzle 161reaches the vicinity of the outer peripheral portion of the wafer W, itis possible to prevent the developing solution Q from falling down tothe outside of the wafer W due to a centrifugal force. Then, thedeveloping solution supply nozzle 161 is moved to the outer peripheralend portion of the wafer W while maintaining the rotational speed of thewafer W at 15 rpm, thereby supplying the developing solution to theentire surface of the wafer W (developing solution supply step, Step T5in FIG. 7). At this time, the liquid film of the diluted developingsolution is formed on the wafer W at Step T3, whereby the dissolvedproduct U is discharged from above the wafer W. Therefore, even if thedeveloping solution Q is supplied onto the wafer W, the generationamount of the dissolved product U is suppressed to a very small amount.As a result, the resist film R existing on the wafer W is developedwithout being affected by the dissolved product U.

Thereafter, if the developing solution supply nozzle 161 reaches theouter peripheral end portion of the wafer W, the supply of thedeveloping solution Q from the developing solution supply nozzle 161 andthe rotation of the developing solution supply nozzle 161 are stopped(time t₆ in FIG. 8). The developing solution supply nozzle 161 isretracted from above the wafer W. Even after the supply of thedeveloping solution Q is stopped, the rotation of the wafer W may bemaintained for a while in order to make uniform the developing solutionQ existing on the wafer W.

Subsequently, if the developing process is completed, the rotationalspeed of the wafer W is reduced to stop the wafer W. Then, the purewater is supplied from, for example, the pure water supply nozzle 154onto the wafer W. Thus, the rinsing process of the wafer W is performed(Step T6 in FIG. 7). Consequently, the developing solution Q and thedissolved resist are washed away and the developing process iscompleted.

After the completion of the developing process, the wafer W istransferred to the heat treatment apparatus 42 by the wafer transferdevice 70 and is subjected to post baking (Step S6 in FIG. 7). Then, thetemperature of the wafer W is adjusted by the heat treatment apparatus43. Thereafter, the wafer W is transferred to the cassette C of apredetermined cassette mounting plate 21 by virtue of the wafer transferdevice 70 and the wafer transfer device 23, whereby a series ofphotolithography steps are completed.

According to the embodiment described above, the liquid pool of thediluted developing solution M is first formed in the central portion ofthe wafer W. Then, the wafer W is accelerated to the first rotationalspeed, thereby diffusing the liquid pool on the entire surface of thewafer W and forming the liquid film of the diluted developing solution Mon the surface of the wafer W (Step T3). At this time, the dissolvedproduct U is formed on the wafer W by the diluted developing solution M.By accelerating the wafer W to the first rotational speed, the diluteddeveloping solution M and the dissolved product U are discharged fromabove the wafer W. Then, the liquid film of the developing solution Q isformed between the wafer W and the developing solution supply nozzle 161which includes the lower end surface 161 a (the liquid contact surface),for example, parallel to the wafer W. The wafer W is rotated whilecontinuing to supply the developing solution from the developingsolution supply nozzle 161. The developing solution supply nozzle 161 ismoved from the central portion of the wafer W to the outer peripheralportion thereof, thereby coating the developing solution Q on the entiresurface of the wafer W. At this time, the resist film R is developedwithout being affected by the dissolved product U because the dissolvedproduct U has already been removed by the diluted developing solution Mat Step T3. As a result, as illustrated in FIG. 16, even when thedeveloping time is made shorter than that of the prior art, it ispossible to perform the developing process with increased in-planeuniformity. FIG. 16 is a view in which the degree of a variation in theline width of the resist pattern within the plane of the wafer W whenthe developing process is performed for 30 seconds using the developingmethod according to the present embodiment is illustrated by colorshading on a shot-by-shot basis. It can be confirmed that in FIG. 16,the variation in the line width is suppressed substantially at the samelevel as that of FIG. 27 in which the developing time is set at 60seconds as described earlier. Therefore, according to the presentdisclosure, it is possible to improve the throughput of the developingprocess while securing the in-plane uniformity of the developingprocess.

Since the developing solution supply nozzle 161 is moved toward theouter peripheral portion of the wafer W while rotating the developingsolution supply nozzle 161 in the direction opposite to the rotationdirection of the wafer W, it is possible to stir the developing solutionQ on the wafer W and to perform the developing process with increasedin-plane uniformity. It is not necessarily required to perform therotation of the developing solution supply nozzle 161. According to thestudy conducted by the present inventors, it was confirmed that evenwhen the rotation of the developing solution supply nozzle 161 is notperformed, it is possible to realize the desired developing accuracy.

A resist for immersion exposure employed in recent years has a largecontact angle with a developing solution. Thus, it is not easy touniformly coat a developing solution on a resist film. However, if thewafer W is pre-wetted by initially diffusing the liquid pool of thediluted developing solution M on the entire surface of the wafer Wthrough the high-speed rotation of the wafer W as in the presentembodiment, it is possible to expect an effect of reducing the contactangle between the resist film R and the developing solution Q (an effectof improving the wettability of the developing solution with respect tothe resist film). As a result, it is possible to supply the developingsolution to the wafer W with increased in-plane uniformity. This makesit possible to further improve the uniformity of the developing processin the wafer plane. Since the contact angle between the resist film Rand the developing solution Q becomes small, it is possible to reducethe supply amount of the developing solution Q. According to the studyconducted by the present inventors, it was confirmed that while about 80cc of the developing solution Q is needed in the prior art in order todevelop the wafer W of, e.g., 300 mm in size, the use of the developingmethod of the present embodiment makes it possible to reduce the supplyamount of the developing solution Q to about 43 cc.

Since the diluted developing solution M diluted with the pure water isused when pre-wetting the wafer W, there is no possibility thatdevelopment occurs only in the dropping position of the diluteddeveloping solution M, namely in the central portion of the wafer W inthe present embodiment. Accordingly, in this respect, it is possible todevelop the wafer W with increased in-plane uniformity.

In the embodiment described above, when forming the liquid pool of thediluted developing solution M at Step T2, the dilution-purposedeveloping solution Q is supplied onto the liquid pool of the pure waterP. However, the method of forming the liquid pool of the diluteddeveloping solution M is not limited to the content of the presentembodiment. For example, the diluted developing solution M diluted withthe pure water in advance may be supplied to the dilution-purposedeveloping solution supply nozzle 158. For example, as illustrated inFIG. 17, the liquid pool of the diluted developing solution M may beformed by directly supplying the diluted developing solution M in theform of the resist film R. By doing so, it is possible to omit Step T1at which the liquid pool of the pure water P is formed. This makes itpossible to further improve the throughput of the developing process. Inthis case, the dilution-purpose developing solution supply nozzle 158serves as a diluted developing solution supply nozzle.

In the embodiment described above, when forming the liquid film of thediluted developing solution M at Step T3, the developing solution Q issupplied from the dilution-purpose developing solution supply nozzle158. However, the supply of the developing solution Q at the time offorming the liquid film of the diluted developing solution M may beperformed by the developing solution supply nozzle 161. In this case,for example, as illustrated in FIG. 18, the developing solution supplynozzle 161 is brought into contact with the liquid pool of the purewater P. In this state, the dilution-purpose developing solution Q issupplied. Thus, the developing solution Q is diluted by the pure waterP. The liquid film of the diluted developing solution M is formed on thewafer W by rotating the wafer W at the first rotational speed at StepT3.

When forming the liquid film of the diluted developing solution M withthe developing solution supply nozzle 161, the diluted developingsolution M may be supplied from the developing solution supply nozzle161. As illustrated in FIG. 19, the liquid pool of the diluteddeveloping solution M may be directly formed between the wafer W and thedeveloping solution supply nozzle 161. Even in this case, the liquidfilm of the diluted developing solution M is formed on the wafer W byrotating the wafer W at the first rotational speed at Step T3.

In the case where both the developing solution Q and the diluteddeveloping solution M are supplied from the developing solution supplynozzle 161, a developing solution pipe 250 for supplying the developingsolution Q and a diluted developing solution pipe 251 for supplying thediluted developing solution M are connected to the developing solutionsupply nozzle 161 as illustrated in FIG. 20. Furthermore, in the casewhere the rotary drive mechanism 162 is not installed in the developingsolution supply nozzle 161, the developing solution pipe 250 and thediluted developing solution pipe 251 may be merged within the developingsolution supply nozzle 161 as illustrated in FIG. 21. In this case, thedeveloping solution supply nozzle 161 illustrated in FIGS. 20 and 21serves also as a diluted developing solution supply nozzle. In otherwords, the supply hole 161 b is shared by the developing solution supplynozzle 161 and the diluted developing solution supply nozzle.

In the embodiment described above, the supply hole 161 b is formed onlyin the central portion of the developing solution supply nozzle 161.However, for example, as illustrated in FIG. 22, a plurality of supplyholes 161 b may be formed on the lower end surface 161 a of thedeveloping solution supply nozzle 161. By forming the plurality ofsupply holes 161 b, it is possible to uniformly supply the developingsolution Q or the diluted developing solution M to the lower end surface161 a.

In the embodiment described above, the pure water supply nozzle 154, thedilution-purpose developing solution supply nozzle 158 and thedeveloping solution supply nozzle 161 are respectively supported bydifferent arms 151, 152 and 153. However, the pure water supply nozzle154, the dilution-purpose developing solution supply nozzle 158 and thedeveloping solution supply nozzle 161 may be supported by a singlearbitrary arm. In this case, for example, as illustrated in FIG. 23, apure water pipe 252 for supplying the pure water P may be installed inthe developing solution supply nozzle 161.

In the embodiment described above, at step T4, the developing solution Qis supplied from the developing solution supply nozzle 161 disposed atthe central portion of the wafer W, thereby forming the liquid pool atthe central portion of the wafer W. Thereafter, the developing solutionsupply nozzle 161 is moved from the central portion of the wafer Wtoward the outer peripheral end portion thereof while supplying thedeveloping solution Q, thereby supplying the developing solution to theentire surface of the wafer W. However, the method of supplying thedeveloping solution Q to the entire surface of the wafer W is notlimited to the content of the present embodiment. For example, asillustrated in FIG. 24, the liquid pool of the developing solution Q maybe formed in the outer peripheral end portion of the wafer W by thedeveloping solution supply nozzle 161 at step T4. Thereafter, thedeveloping solution supply nozzle 161 is moved to the central portion ofthe wafer W while supplying the developing solution Q, thereby supplyingthe developing solution Q to the entire surface of the wafer W. Even inthis case, it is possible to develop the resist film R without beingaffected by the dissolved product U because the dissolved product U hasalready been discharged from above the wafer W together with the diluteddeveloping solution M at step T3

According to the study conducted by the present inventors, it wasconfirmed that the in-plane uniformity of the developing process isimproved by moving the developing solution supply nozzle 161 from theouter peripheral end portion of the wafer W toward the center portionthereof as illustrate in FIG. 24. The reason is supposed as follows.Since the dilution developing solution M is supplied to the centerportion of the wafer W at step T3, a slight difference in the contacttime with the diluted developing solution M is generated in the centralportion of the wafer W and the outer peripheral portion thereof.Furthermore, the development occurs slightly by the developing solutionM also. Therefore, the line width tends to become slightly thicker inthe outer peripheral portion of the wafer W than in the central portionthereof. By forming the liquid pool of the developing solution Q in theouter peripheral end portion of the wafer W and then moving thedeveloping solution supply nozzle 161 toward the central portion of thewafer W as illustrated in FIG. 24, the difference in the contact timewith the diluted developing solution M, which is generated at step T3,is mitigated. Thus, it is supposed that the in-plane uniformity of thedeveloping process is further improved.

According to the present disclosure in some embodiments, it is possibleto improve the throughput of the developing process while securing thein-plane uniformity of the developing process.

While some preferred embodiments of the present disclosure have beendescribed with reference to the accompanying drawings, the presentinvention is not limited to these embodiments. It will be apparent tothose skilled in the art that different changes or modifications may beconceived without departing from the spirit of the present disclosuredefined in the claims. It is to be understood that these changes ormodifications may well fall within the technical scope of the presentdisclosure. The present disclosure is not limited to the aforementionedembodiments but may employ different forms. The present disclosure maybe applied to a case where the substrate is a substrate other than thewafer, such as a flat panel display (FPD), a mask reticle for a photomask or the like.

The present disclosure is useful when developing a resist film formed ona substrate.

What is claimed is:
 1. A developing method for supplying a developingsolution onto a substrate and developing a resist film formed on thesubstrate and provided with a predetermined exposed pattern, comprising:forming a liquid pool of a diluted developing solution diluted with purewater in a central portion of the substrate; after forming the liquidpool, forming a liquid film of the diluted developing solution on asurface of the substrate by accelerating rotation of the substrate todiffuse the liquid pool of the diluted developing solution on the entiresurface of the substrate; and after forming the liquid film, supplyingthe developing solution onto the substrate, supplying the developingsolution including: supplying the developing solution from a developingsolution supply nozzle having a liquid contact surface while securing agap having a predetermined size between the developing solution supplynozzle and the substrate; and moving the developing solution supplynozzle in a radial direction passing through a center of the substratewhile forming a liquid pool of the developing solution between thesubstrate and the liquid contact surface of the developing solutionsupply nozzle.
 2. The method of claim 1, wherein in supplying thedeveloping solution, a start point of the movement of the developingsolution supply nozzle is the central portion of the substrate and anend point of the movement of the developing solution supply nozzle is anouter peripheral portion of the substrate.
 3. The method of claim 1,wherein in supplying the developing solution, a start point of themovement of the developing solution supply nozzle is an outer peripheralportion of the substrate and an end point of the movement of thedeveloping solution supply nozzle is the central portion of thesubstrate.
 4. The method of claim 1, wherein the formation of the liquidpool of the diluted developing solution in forming a liquid pool isperformed by forming a liquid pool of the pure water by supplying thepure water to the central portion of the substrate which is notrotating, and then supplying a dilution-purpose developing solution ontothe liquid pool of the pure water.
 5. The method of claim 1, wherein theformation of the liquid pool of the diluted developing solution informing a liquid pool is performed by supplying the diluted developingsolution diluted with the pure water in advance to the central portionof the substrate which is not rotating.
 6. The method of claim 1,wherein the movement of the developing solution supply nozzle insupplying the developing solution is performed while rotating a lowersurface of the developing solution supply nozzle in a direction oppositeto a rotation direction of the substrate.
 7. The method of claim 1,wherein forming a liquid film includes accelerating the substrate to afirst rotational speed to diffuse the liquid pool of the diluteddeveloping solution on the entire surface of the substrate, andsupplying the developing solution includes moving the developingsolution supply nozzle from the central portion of the substrate to anouter peripheral portion of the substrate while rotating the substrateat a second rotational speed lower than the first rotational speed. 8.The method of claim 7, wherein the first rotational speed is from 1,500rpm to 2,000 rpm and the second rotational speed is from 15 rpm to 30rpm.
 9. The method of claim 7, wherein in forming a liquid film, thesubstrate, which is not rotating, is accelerated to a third rotationalspeed lower than the first rotational speed, then the substrate isdecelerated to a fourth rotational speed lower than the third rotationalspeed, and then the substrate is accelerated to the first rotationalspeed.
 10. The method of claim 9, wherein the third rotational speed isfrom 200 rpm to 400 rpm.
 11. A non-transitory computer-readable storagemedium which stores a program that operates on a computer of a controlpart configured to control a developing apparatus so as to cause thedeveloping apparatus to perform the developing method of claim
 1. 12. Adeveloping apparatus for supplying a developing solution onto asubstrate and developing a resist film formed on the substrate andprovided with a predetermined exposed pattern, comprising: a substrateholding part configured to hold a rear surface of the substrate and torotate the held substrate about a vertical axis; a developing solutionsupply nozzle including a liquid contact surface and a supply holeconfigured to supply the developing solution to the liquid contactsurface; a moving mechanism configured to move the developing solutionsupply nozzle; a pure water supply nozzle configured to supply purewater onto the substrate; and another moving mechanism configured tomove the pure water supply nozzle.
 13. A developing apparatus forsupplying a developing solution onto a substrate and developing a resistfilm formed on the substrate and provided with a predetermined exposedpattern, comprising: a substrate holding part configured to hold a rearsurface of the substrate and to rotate the held substrate about avertical axis; a developing solution supply nozzle including a liquidcontact surface and a supply hole configured to supply the developingsolution to the liquid contact surface; a moving mechanism configured tomove the developing solution supply nozzle; a diluted developingsolution supply nozzle configured to supply a diluted developingsolution onto the substrate; and another moving mechanism configured tomove the diluted developing solution supply nozzle.
 14. The apparatus ofclaim 13, wherein the supply hole is shared by the developing solutionsupply nozzle and the diluted developing solution supply nozzle.